Starting bar for horizontal continuous casting apparatus

ABSTRACT

A STARTING BAR FOR USE WITH A HORIZONTAL CONTINUOUS CASTING MOLD INCLUDES AN ELONGATE MEMBER HAVING SURFACE GROOVES ADJACENT THE END TO BE INSERTED INTO THE MOLD, WITH WEARING PIECES SECURED IN THE GROOVES TO MAINTAIN THE END OF THE BAR IN SPACED RELATION FROM THE WALLS OF THE MOLD. RESILIENT MATERIAL DISPOSED BETWEEN THE END OF THE BAR AND A CAP PIECE IS COMPRESSED TO ENGAGE THE WALLS OF THE MOLD AND FORM A SEAL.   D R A W I N G

United States Patent Joseph .I. Ciochetto Allison Park, Pa. 743,730

July 10, 1968 June 28, 1971 Koppers Company, Inc.

Inventor Appl. No. Filed Patented Assignee STARTING BAR FOR HORIZONTAL CONTINUOUS CASTING APPARATUS 7 Claims, 3 Drawing Figs.

US. Cl 164/274, 164/83 Int. Cl 822d 11/08 Field of Search 164/274,

[56] References Cited UNITED STATES PATENTS 3,351,125 '1 H1967 Silva 175/274 3,080,625 3/1963 Pearson et al. 164/274 FOREIGN PATENTS 998,796 7/1965 Great Britain 164/282 Primary Examiner.l. Spencer Overholser Assistant Examiner-lohn S. Brown Attorneys-Sherman H. Barber and Olin E. Williams ABSTRACT: A starting bar for use with a horizontal continuous casting mold includes an elongate member having surface grooves adjacent the end to be inserted into the mold, with wearing pieces secured in the grooves to maintain the end of the bar in spaced relation from the walls of the mold. Resilient material disposed between the end of the bar and a cap piece is compressed to engage the walls of the mold and form a seal.

PATENTED JUN28 I971 3.587.716

- 77 I mvsmom FIG 2 JOSEPH J. (/(ICHETTO SWD W STARTING BAR FOR HORIZONTAL CONTINUOUS CASTING APPARATUS BACKGROUND OF THE INVENTION This invention relates to continuous metal casting, and more particularly, to a starting bar for use with horizontal continuous metal casting apparatus.

Horizontal continuous castingoffers many features and advantages over conventional vertical continuous casting, and over the curved-mold, or so-called low-head, type of continuous casting apparatus.

One of the many features and advantages is that horizontal continuous casting obviates the need for deep pits, or excessively high casting towers, to accommodate vertical casting equipment. Another feature and advantage is that there is no need to provide a curved casting mold nor an elaborate curved apron structure, nor conventional bending and straightening equipment, that are associated with vertical continuous casting machines and casting machines of the low-head type.

Heretofore, horizontal continuous casting machines have experienced some problems related to mold design and to mold cooling. Further, a-horizontal continuous casting mold, made of copper in the usual manner, has been subjected to considerable wear due to the starting bar scoring the walls of the mold when the bar is inserted and withdrawn from the mold.

How the present invention overcomes the difficulties experienced with starter bars like those found in the prior art will become evident to those skilled in the art from the following specification and drawing.

SUMMARY OF THE INVENTION A starting bar in accordance with the invention comprises an elongate member having surface grooves adjacent the end to be inserted into a continuous casting mold. Wearing pieces of relatively soft material are secured in the grooves to main tain the bar spaced apart from the walls of the mold. Resilient material is compressed between a cap at the end of the bar to form a seal with the mold walls and prevent the flow of molten metal past the sealing material.

For a further understanding of the invention and for addi tional features and advantages thereof, reference may be made to the following description and drawing which illustrates a preferred embodiment of the equipment shown only for the purpose of exemplification.

BRIEF DESCRIPTION OF THE DRAWING In the drawing:

FIG. 1 is a schematic sectional elevational view of a portion of a horizontal continuous casting apparatus, including a starting bar in accordance with the invention;

FIG. 2 is a plan view of the head end portion of the starting bar ofFlG. I; and

FIG. 3 is a cross-sectional view along line III-III of FIG. 1.

DETAILED DESCRIPTION In the drawing, FIG. 1 illustrates a portion of a horizontal continuous casting apparatus that is similar to that described in my copending application Ser. No. 734,332 filed June 4, 1968, which application is owned commonly with this present application. Such apparatus includes a tundishlike vessel 11 into which molten metal 13 is being teemed from a conventional ladle 15. The tundishlike vessel 11 has a cover 17 through which a tube 19 extends into the vessel 11, and which is connected to degassing and pressure control equipment (not shown).

The tundishlike vessel 11 is secured to a suitable foundation 2], and has both a bottom drain outlet 23 that is normally sealed closed and a bottom side outlet 25 that cooperates with a horizontal continuous casting mold 27. The bottom outlet 23 may be opened in emergency when it is necessary to dump molten metal into a suitable vessel 29 located below the outlet 23, or when it is desirable to drain molten metal and residue material during maintenance and repair periods.

The horizontal continuous casting mold 27 includes a water-cooled fixed first sleeve portion 31 having an end that cooperates with the side outlet 25, and which integrally joins with an open trough potion 33. The open trough portion 33 of the mold 27 is covered by a movable second portion or cover 35 to which is attached a vibrator 37.

The mold 27 is secured to the foundation 21, and two or more side supports 39 are, or may be, secured to the foundation 21 to maintain the casting mold 27in a fixed position relative to the tundishlike vessel 11.

The movable cover 35 is restrained by the sidewalls of the trough portion 33, and is resiliently mounted so as to move vertically under the influence of the vibrator 37.

Associated with the continuous casting apparatus described previously is astarting bar 41 which is used to seal temporarily the entrance end of the casting mold 27, and to provide a tool whereby a cast strand formed in'the mold can be continuously withdrawn.

The starting bar 41 comprises an elongate rectangular bar of steel, preferably, that has cross-sectional dimensions that are slightly smaller than the cross-sectional dimensions of the passage through the fixed portion 31 of the mold 27; the end portion of the starting bar that is within the casting mold is designated a head portion 43.

The head portion 43 of the starting bar 41 is chamfered, as shown at 45 (FIG. 2), to provide a forward projection 47 of reduced peripheral dimensions. There is an axial hole 49 in the head end 43 that slidably accommodates an internally threaded sleeve 51.

A stud 53 is threaded into the sleeve 51 and extends forward of the forward projection 47. A metallic cap 55, which may be of any suitable material, but which is made of meehanite in a preferred embodiment of the invention, has a hole 57 therethrough and a counterbore recess 59 which accommodates the outer end of the sleeve 51, as shown in FIG. 2.

A single guide pin 61 or dowel is threaded into the forward projecting portion 47 and is received in a hole 63 in a cap 55, wherefore the cap 55 is located and maintains its position with respect to the head end 43 of the starting bar 41.

Both the sleeve 51 and the starting bar head end portion 43 have matching holes in which a pin 83 resides to interconnect the sleeve 51 and the starting bar head end portion 43. Another hole 65 in the stud 53 is for engaging a torque bar to remove the stud 53 from the nut 67 after the sleeve 51 is unscrewed from the stud 53 when the assembly is to be disassembled.

The other end of the stud 53 is threaded to receive a large nut 67 that is threaded onto the stud in such a way that the end of the stud 53 does not project beyond the top surface of the nut 67. Preferably, there is a cavity in the top of the nut which is filled with suitable refractory material 69.

Between the nuts 67 and the cap 55 there is a ceramic tubular sleeve 71 that loosely surrounds the stud 53. Of course, the sleeve may be made of any other suitable material, such as meehanite or the like if such material is preferred.

Between the cap 55 and the chamfered end 45 of the head end portion 43, there is a heat-resistant ring 73 made of resilient material, such as formed asbestos, or similar suitable substance.

The outer surface of the starting bar 41, which may have a rectangular cross section as shown in FIG. 3, or a cross section of any other form, therein has one or more longitudinal grooves 75 that extend some distance backward from the vchamfered end 45, as shown in FIG. 1. The grooves 75 extend grooves 75, at intervals along its length, by means of capscrews 79, preferably those having a socket 81 therein'to receive a tool to tighten and loosen the capscrews. While in a preferred embodiment of the invention, elongate strips of relatively soft material are preferred, it is to be understood that the grooves need not be continuous in length, and that the strips of relatively soft material need not be continuous in length. A plurality of relatively short-length grooves. and short, spaced-apart, lengths of soft material may be secured to the surface of the bar 41, if such an arrangement is preferred.

While the starting bar 41, shown in FIG. 1, has a uniform cross-sectional dimension, throughout its length, it will be understood by those skilled in the art that the cross-sectional dimensions of the portion of the starting bar extending outside the mold cavity may have a smaller cross-sectional dimension than the head end portion 43 of the starting bar which is inserted into the mold..

Further, while the head end portion 43, preferably, has a hollow central cavity 85 to reduce its weight, the reduced cross-sectional portion of the starting bar connected to the head end portion 43 may be either solid or hollow, as preferred.

ln operation, the starting bar 41 of the invention is first assembled and then inserted into the mold to a location about as shown in FIG. 1.

At first the nut 67 is threaded onto the limited thread-length of the outer end of the stud 53 so that the nut 67 makes ajamb fit, yet leaves the cavity mentioned before that is filled with refractory material 69 or other suitable plug material.

With the internally threaded sleeve 51 positioned in the hole 49 and locked to the starting bar head end portion 43 by the removable pin 83, the cap 55 is so placed that the counter bore recess 59 engages the end of the sleeve 51 and the locat ing pin 61 fits in the hole 63.

Then, the stud 53 with the nut 67 is inserted through the sleeve 71 and hole 57 of the cap 55, is threaded into the sleeve 51 until the heat-resistant ring 73 is compressed to give a proper fit with the mold wall cavity to make a tight seal therewith.

As mentioned previously, hole 65 in the end of the stud 53 is used only to engage a torque bar for removing the stud from the nut and for reuse.

The foregoing operations can be carried out before the head end 43 of the starting bar is inserted into the mold, particularly in a horizontal continuous casting mold.

Likewise, before the head end 43 is inserted into the continuous casting mold, grooves 75 in the surfaces of the starting bar 41 are filled with the strip material 77 that is secured in place by capscrews 79.

After the starting bar 41 has been inserted into the mold cavity, to the extent shown in FIG. 1, molten metal may be teemed from the ladle into the tundishlike vessel 11 and the molten metal will solidify around the sleeve and nut, but will not adhere to the cap which is made preferably of meehanite. it is preferred that the cap be made of meehanite since the molten metal will not bond to it and the cap, as well as the sleeve and stud may be reused. v

A feature of the invention is the elongate strip of relatively soft material that is inserted into the surface grooves of the starting bar head portion. These inserts are in contact with the mold walls and they prevent the metallic portion of starting bar from contacting the mold walls themselves. The strip material, being softer than the material of which the mold walls are made, wears faster than the mold walls and will prevent scoring, scraping, damaging of the mold'walls when the head end portion of the starting bar is inserted into and retracted from the mold.

A feature ofthe invention is that the cap and stud, as well as the sleeve, if it is made of ceramic or meehanite material, may be recovered and reused throughout several heats.

A feature of the invention is that the head end portion of the starting bar, including the sealing ring, may be assembled in a convenient location prior to introduction of the head end por- LII tion of the starting bar into the mold. This obviates the requirement for manually sealing :the end of the conventional starting bars with a refractory paste or the like as is customary in prior art practice.

A feature of the invention is that the elongate guide strips keep the head end portion of the starting bar coaxial with the mold cavity.

A feature of the invention is that the elongate guide strips prevent the overhanging weight of the starting bar from unduly compressing the heat-resistant ring.

Although the invention has been described herein with a certain degree of particularity, it is understood that the present disclosure has been made only as an example and that the scope of the invention is defined by what is hereinafter claimed.

lclaim:

l. A starting bar for use with a continuous casting mold comprising:

a. an elongate member having grooves extending longitudinally in its surfaces adjacent one end thereof; in its b. means cooperating with said grooves to maintain said starting bar spaced apart from the walls of said mold;

c. means to form a seal between the end of said starting bar and said mold when said one end of said starting bar is inserted into said mold; and

d. means to join said starting bar to the solidified metal of a cast strand formed in said mold.

2. The invention of claim 1 wherein:

a. the means cooperating with said grooves are pieces of relatively soft material; and including b. fastener means extending through said material and securing said pieces in said grooves.

3. the invention of claim 1 wherein the means to form a seal includes:

a. movable means positioned adjacent the end of said starting bar that is within said mold;

b. a resilient substance disposed between said movable means and the end ofsaid bar; and

c. adjustable means for compressing said resilient substance so that said resilient material contacts the walls of said mold and forms a seal therewith to prevent molten metal from flowing thereby.

4. The invention of claim 3 wherein said adjustable means includes:

a. a stud secured to said one end and projecting through said movable means; and

b. a nut threaded on said stud and coacting with said movable means.

5. A starting bar for use with a continuous casting mold comprising:

a. an elongate member having grooves extending longitudinally in at least one surface thereof adjacent one end;

b. one or more pieces of relatively soft wearing material lodged in said groove that contacts at least one internal wall of said mold to prevent the elongate member from contacting the walls of said mold;

c. fastener means securing said piece to said elongate member;

d. a stud mounted to said one end;

e. a cap positioned adjacent said one end and having a hole therein through which said stud passes;

f. a sleeve surrounding said stud and engaging said cap on the side away from said one end;

g. resilient sealing material disposed between said cap and said one end; and

h. means to urge said sleeve toward said cap so that said cap compresses said sealing material and urges said sealing material into contact with the walls of said mold when said starting bar is inserted thereinto.

. The invention of claim 5 including:

a sleeve that is pin connected to said stud;

. means securing said sleeve to said one end of said starting bar.

7. The invention of claim 6 including:

said nut between the end of said stud and the top of said nut.

3 3 33" UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 5,587,716 Dated June 2Q 1911 Inventor-(s) Joseph ciochetto It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Claim 1., line 20, delete "in its", second occurence Signed end sealed this 13th day of June 1972.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GO'I'TSCHALK Attesting Officer Commissioner of Patents 

